Topping up a Keg

[maxt50]

Tell me what you think of this is a crazy idea. I have a carbonated keg i would like to take to a party, sadly I have all ready drank a few liters of it. Could I open the lid, top it up with a growler or two of similar style beer, purge with CO2, and be good to go? As long as I purge, will it stay fresh and carbonated?

Thanks for feedback

 

[PADave]

So you want to take your homebrew and mix it with a couple growlers that you bought? Why not just take your keg and the growlers separate? I wouldn't want to do it, but I don't see why it wouldn't work.

 

[maxt50]

That's right, I'd like to top up homebrew with craftbrew growler. I just like the simplicity of taking one full keg and that's it.

 

[JohnSand]

I think there might be a foam problem, and some concern over oxidation. I have added to kegs from other kegs with a jumper, out post to out post slowly. I think a slightly short keg won't disappoint anyone.

 

[PADave]

I still don't see the point. You can't say it's your beer, because it's a mix. You don't know what it will taste like, because it's a quick mix. If you're just looking for volume to get drunk on, why not pick up a case or two of cheep stuff to take? Unless of course the homebrew sucks and you are looking for an easy way to get rid of it.

 

[Kickass]

Looks like you've created an itch that PADave can't help but scratch.

 

[shoengine]

What JohnSand said. Also, do you really need the extra volume?

 

[maxt50]

On second sober thought, you are right it's not worth it. However I still don't understand why most think that it is risky to open and top up a keg, when have to do that will I fill it the first time? I am missing something? is it riskier once it's carbonated for some reason?

Thanks

 

[myndflyte]

On second sober thought, you are right it's not worth it. However I still don't understand why most think that it is risky to open and top up a keg, when have to do that will I fill it the first time? I am missing something? is it riskier once it's carbonated for some reason?

Thanks

Aside from the fact of just mixing two beers together, yes I think the issue is the fact it's already carbonated. It's possible that by dumping in something else it could cause a rapid release of CO2 and a ton of foaming. This is most certainly an issue, for example, if you wanted to add spices to an already carbonated beer. Any granules will create nucleation sites and a huge release of CO2 and could potentially foam over. You'll probably be fine if you do it but you still run that risk.

 

[mongoose33]

On second sober thought, you are right it's not worth it. However I still don't understand why most think that it is risky to open and top up a keg, when have to do that will I fill it the first time? I am missing something? is it riskier once it's carbonated for some reason?

Thanks

If you're drinking it soon, there's no contamination concern; after all, people fill growlers that way all the time.

If you're drinking it soon, oxidation probably won't have had much time to create off-flavors either.

But like others above, I can't see why you'd do this. Did you promise to bring a full keg? And if you add anything else, it's a Frankenstein brew, no longer something that is definitively YOUR beer.

***********

And as far as opening the keg to fill it in the first place, many of us have moved away from that approach to a closed-transfer system into a keg that has been purged of air. Oxygen is the enemy of beer, and keeping it away from beer is job #1 once fermentation is complete. Those who bottle with priming sugar have yeast that consume oxygen in the bottle, but kegging doesn't have that (unless you condition/carb as if it were a big bottle).

To purge a keg, fill it with star-san. Attach a gas line, and let it bubble up from the bottom until the bubbles fill the headspace and allow the lid to be immersed in the bubbles. Attach the lid, and now you have a keg full of Star-san and no air (the bubbles have CO2 in them--but be careful how much you add when "bubbling" as too great a volume of CO2 will gush the star-san out of the keg mouth).

Then, push the Star-san out of the keg w/ CO2 using a jumper to move it to another keg, or similar to move it to a 5-gallon bucket to save for next time. This replaces the star-san with CO2, and now you have a purged keg. No air. Then rack/drain your fermenter into it while opening the PRV to allow the gas to escape. Voila! Good beer in purged keg.

Two pics, one showing how I did that from a plastic fermenter (the gas line is taking the CO2 pushed out by the beer and feeding it back into the fermenter so no air is entering the fermenter), the other how I do a pressure transfer from my Spike conical.

 

[Dade0]

Trust your gut.

Sent from my XT1575 using Home Brew mobile app

 

[KarmaCitra]

Not worth the time nor effort. Too many variables.